Hard disk drives include a recordable medium and a head which is mounted to move above the recordable medium as the medium spins. As hard disk drives are designed to smaller and smaller sizes and the medium is designed to store more and more information on narrower and narrower tracks, it is imperative that the relative positions of the rotating medium and the moving head be monitored and other parameters such as relative motion and speed variations be monitored. Such monitoring is needed in order to correct any errors before they become too great. However, today's monitoring techniques are insufficient for the track widths, height tolerances and other parameters.
Thus, what is needed are robust monitoring and self-adjustment techniques for hard disk drives that are compatible with future ultra-thin, greater storage hard disk drives. Furthermore, other desirable features and characteristics will become apparent from the subsequent detailed description, taken in conjunction with the accompanying drawings and this background of the disclosure.